Electric compressor

Abstract

An electric compressor includes an inverter device having a circuit substrate and a connector. The inverter device includes an inverter circuit and a filter circuit. The filter circuit includes a coil, a first capacitor located between the coil and the connector, and a second capacitor located between the coil and the inverter circuit. The coil, the first capacitor, and the second capacitor are mounted on the circuit substrate. The circuit substrate includes a conductive pattern that electrically connects the first capacitor and the second capacitor, the conductive pattern being grounded, and an insulating portion configured such that the impedance between the first capacitor and the second capacitor in the conductive pattern is greater than the impedance between the second capacitor in the conductive pattern and the ground.

Description

Technical Field

[0001] The present disclosure relates to an electric compressor. Background Art

[0002] An electric compressor includes a compression unit, an electric motor, and an inverter device. The compression unit compresses a fluid. The electric motor drives the compression unit. The inverter device includes a circuit board, which drives the electric motor. The electric compressor also includes a connector, which is electrically connected to a power source. Furthermore, the inverter device includes an inverter circuit, which converts DC power input from the power source via the connector into AC power.

[0003] For example, Japanese Patent Application Publication No. 2019-187228 discloses a converter device including a filter circuit. The filter circuit is located between the converter circuit and the connector and reduces noise. Specifically, the filter circuit includes a coil, a first capacitor, and a second capacitor. The first capacitor is located between the coil and the connector. The second capacitor is located between the coil and the converter circuit. The coil, the first capacitor, and the second capacitor are mounted on a circuit substrate. The circuit substrate includes a conductive pattern. The conductive pattern electrically connects the first capacitor and the second capacitor. The conductive pattern is connected to ground.

[0004] Furthermore, noise generated by the converter circuit flows to the ground (earth) via the coil, the first capacitor, and the conductive pattern, or flows to the ground via the second capacitor and the conductive pattern. This prevents noise generated by the converter circuit from flowing to the connector. Consequently, leakage of noise generated by the converter circuit to the outside via the connector is suppressed. Summary of the Invention

[0005] Problems to be solved by the invention

[0006] In such an electric compressor, noise flowing from the inverter circuit to the conductive pattern via the second capacitor may flow toward the connector via the first capacitor. When noise generated by the inverter circuit flows to the connector, it may leak to the outside through the connector. Therefore, in such an electric compressor, it is desirable to prevent noise generated by the inverter circuit from leaking to the outside through the connector.

[0007] Technical solutions to problems

[0008] A technical solution of the present disclosure relates to an electric compressor comprising: a compression section configured to compress a fluid; an electric motor configured to drive the compression section; an inverter device having a circuit substrate for driving the electric motor; and a connector electrically connected to a power supply. The inverter device comprises: a converter circuit configured to convert DC power input from the power supply via the connector into AC power; and a filter circuit located between the converter circuit and the connector and configured to reduce noise. The filter circuit comprises: a coil; a first capacitor located between the coil and the connector; and a second capacitor located between the coil and the converter circuit. The coil, the first capacitor, and the second capacitor are mounted on the circuit substrate. The circuit substrate comprises a conductive pattern electrically connecting the first capacitor and the second capacitor, the conductive pattern being grounded. The circuit substrate comprises an insulating portion configured to make the impedance between the first capacitor and the second capacitor in the conductive pattern greater than the impedance between the second capacitor in the conductive pattern and the ground.

[0009] Thus, the insulating portion increases the impedance between the first and second capacitors in the conductive pattern compared to the impedance between the second capacitor and ground. Consequently, noise flowing from the converter circuit to the conductive pattern via the second capacitor is less likely to flow through the first capacitor toward the connector. Furthermore, noise flowing from the converter circuit to the conductive pattern via the second capacitor is more likely to flow to ground. As a result, noise generated by the converter circuit is prevented from leaking externally through the connector.

[0010] In the above-mentioned electric compressor, the conductive pattern may be formed with a gap extending from between the first capacitor and the second capacitor toward the ground, and the insulating portion may include the gap.

[0011] Thus, the insulation portion can be achieved simply by forming a gap in the conductive pattern extending from the first capacitor to the ground between the second capacitor. This eliminates the need to add new coils, capacitors, etc. to the circuit board to prevent noise generated by the inverter circuit from leaking to the outside through the connector. This avoids the creation of new noise paths on the circuit board caused by adding new coils, capacitors, etc.

[0012] Effects of the Invention

[0013] According to the present disclosure, it is possible to suppress the noise generated from the inverter circuit from leaking to the outside via the connector. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a cross-sectional view of the electric compressor in the embodiment.

[0015] Figure 2 It shows Figure 1 Circuit diagram of the electrical composition of the electric compressor.

[0016] Figure 3 This is a plan view of the circuit board.

[0017] Description of Reference Numerals

[0018] B…power storage device serving as a power source, 10…electric compressor, 31…compression unit, 32…electric motor, 36…connector, 40…inverter device, 41…circuit board, 42…inverter circuit, 44…filter circuit, 46…coil, 47…first capacitor, 48…second capacitor, 53…third conductive pattern serving as a conductive pattern, 56…gap, 57…insulating portion. DETAILED DESCRIPTION

[0019] The following, according to Figures 1 to 3 An embodiment in which an electric compressor is embodied will be described. The electric compressor of this embodiment is used in, for example, a vehicle air conditioner.

[0020] (Overall Structure of Vehicle Ve)

[0021] like Figure 1 As shown, the vehicle Ve includes a power storage device B and a vehicle air conditioner 100. The power storage device B is a power source that supplies power to devices mounted on the vehicle Ve. The power storage device B is a DC power source. The power storage device B is, for example, a secondary battery or a capacitor. The vehicle air conditioner 100 includes an external refrigerant circuit 110, an air conditioner ECU 120, and an electric compressor 10. The external refrigerant circuit 110 supplies a refrigerant as a fluid to the electric compressor 10. The external refrigerant circuit 110 includes, for example, a heat exchanger and an expansion valve. The external refrigerant circuit 110 cools and heats the interior of the vehicle Ve by exchanging heat between the outside and the refrigerant. The air conditioner ECU 120 is configured to grasp the vehicle interior temperature, the set temperature of the vehicle air conditioner, and the like. Furthermore, the air conditioner ECU 120 sends various commands, such as on / off, to the electric compressor 10 based on parameters such as the vehicle interior temperature and the set temperature of the vehicle air conditioner.

[0022] (Overall Structure of Electric Compressor 10)

[0023] The electric compressor 10 includes a housing 20, a rotating shaft 30, a compression unit 31, an electric motor 32, a connector 36, and an inverter device 40. The housing 20 is made of metal. For example, the housing 20 is made of aluminum. The housing 20 can be made of any metal as long as it has thermal conductivity. The housing 20 is grounded to the vehicle body (not shown) of the vehicle Ve.

[0024] The housing 20 includes an intake housing member 21, a discharge housing member 22, and a cover member 23. The intake housing member 21 includes a plate-shaped end wall 21a, a cylindrical peripheral wall 21b, and an intake port 21c. The peripheral wall 21b extends from the outer periphery of the end wall 21a toward the discharge housing member 22. The intake port 21c is connected to the external refrigerant circuit 110. The intake port 21c is provided on the peripheral wall 21b.

[0025] The discharge housing member 22 is assembled to the suction housing member 21 so as to block the opening of the suction housing member 21. Thus, the suction housing member 21 and the discharge housing member 22 form a motor accommodation chamber S1 within the housing 20. The discharge housing member 22 has a discharge port 22a. The discharge port 22a is connected to the external refrigerant circuit 110.

[0026] The cover member 23 has a plate-shaped end wall 23a and a cylindrical peripheral wall 23b. The cover member 23 is attached to the end wall 21a of the suction housing member 21 so that the open end of the peripheral wall 23b abuts the end wall 21a. The opening of the peripheral wall 23b of the cover member 23 is blocked by the end wall 21a. Thus, the end wall 21a and the cover member 23 form the inverter housing chamber S2. Therefore, the housing 20 has the inverter housing chamber S2. The end wall 21a separates the motor housing chamber S1 from the inverter housing chamber S2.

[0027] The rotating shaft 30 is rotatably arranged relative to the housing 20. The rotating shaft 30 is rotatably supported by the housing 20. The rotating shaft 30 is housed in the motor housing chamber S1 such that the axial direction of the rotating shaft 30 coincides with the axial direction of the peripheral wall 21b.

[0028] (Configuration of Compression Unit 31)

[0029] The compression unit 31 is housed within the suction housing member 21. The compression unit 31 is a scroll-type unit, for example, comprising a fixed scroll (not shown) fixed within the suction housing member 21 and a movable scroll (not shown) opposing the fixed scroll. The compression unit 31 is positioned within the motor housing chamber S1 closer to the discharge port 22a than the suction port 21c. The compression unit 31 is coupled to the rotating shaft 30. The rotation of the rotating shaft 30 drives the compression unit 31 to compress the refrigerant.

[0030] (Configuration of Electric Motor 32)

[0031] The electric motor 32 is housed in the motor housing chamber S1. The electric motor 32 is positioned between the compression section 31 and the end wall 21a within the motor housing chamber S1. The electric motor 32 includes, for example, a cylindrical rotor 33, a stator 34, and three-phase coils 35u, 35v, and 35w. The rotor 33 is fixed to the rotating shaft 30. Thus, the rotating shaft 30 is configured to rotate integrally with the rotor 33. The stator 34 is fixed to the peripheral wall 21b of the housing 20. The rotor 33 and stator 34 face each other in the radial direction of the rotating shaft 30.

[0032] The three-phase coils 35u, 35v, and 35w are each wound around the stator 34. The three-phase coils 35u, 35v, and 35w are, for example, Y-connected. The connection method of the three-phase coils 35u, 35v, and 35w is not limited to Y-connection but can be any connection method. For example, the three-phase coils 35u, 35v, and 35w may also be delta-connected.

[0033] The three-phase coils 35u, 35v, and 35w are energized in a predetermined pattern, causing the rotor 33 to rotate. Furthermore, the rotating shaft 30 rotates in conjunction with the rotation of the rotor 33. This drives the compression unit 31. Therefore, the electric motor 32 drives the compression unit 31. Furthermore, the refrigerant flowing through the external refrigerant circuit 110 is sucked into the shell 20 through the suction port 21c. The compression unit 31 compresses the refrigerant sucked into the shell 20. The compressed refrigerant is discharged from the discharge port 22a to the external refrigerant circuit 110.

[0034] (Regarding connector 36)

[0035] The connector 36 is a terminal for supplying electric power from the power storage device B mounted on the vehicle Ve to the inverter device 40 . The connector 36 is electrically connected to the power storage device B. The connector 36 is provided on the cover member 23 .

[0036] (Overall Structure of Inverter Device 40)

[0037] Inverter device 40 is housed in inverter housing chamber S2 . Therefore, housing 20 houses inverter device 40 . Inverter device 40 is electrically connected to power storage device B via connector 36 .

[0038] The inverter device 40 includes a circuit board 41. The circuit board 41 drives the electric motor 32. The circuit board 41 is housed in the inverter housing chamber S2. The circuit board 41 faces the end wall 21a with a predetermined gap in the axial direction of the rotating shaft 30. The circuit board 41 is housed in the inverter housing chamber S2 such that the thickness of the circuit board 41 is aligned with the axial direction of the rotating shaft 30.

[0039] like Figure 2 As shown, the inverter device 40 includes an inverter circuit 42 , a control unit 43 , and a filter circuit 44 .

[0040] (Regarding Converter Circuit 42)

[0041] The converter circuit 42 includes a positive bus Lp, a negative bus Ln, six switching elements Q1 to Q6, and six diodes D1 to D6. IGBTs are used as the switching elements Q1 to Q6. Between the positive bus Lp and the negative bus Ln, the switching element Q1 constituting the u-phase upper arm and the switching element Q2 constituting the u-phase lower arm are connected in series. Between the positive bus Lp and the negative bus Ln, the switching element Q3 constituting the v-phase upper arm and the switching element Q4 constituting the v-phase lower arm are connected in series. Between the positive bus Lp and the negative bus Ln, the switching element Q5 constituting the w-phase upper arm and the switching element Q6 constituting the w-phase lower arm are connected in series. Diodes D1 to D6 are connected in antiparallel to the switching elements Q1 to Q6.

[0042] The u-phase coil 35u of the electric motor 32 is connected between switching elements Q1 and Q2. The v-phase coil 35v of the electric motor 32 is connected between switching elements Q3 and Q4. The w-phase coil 35w of the electric motor 32 is connected between switching elements Q5 and Q6. Inverter circuit 42, which includes switching elements Q1 to Q6 forming upper and lower arms, is configured to convert a DC voltage into an AC voltage in response to the switching operation of switching elements Q1 to Q6, and output the voltage to the electric motor 32. Therefore, inverter circuit 42 converts DC power input from power storage device B via connector 36 into AC power.

[0043] (Regarding the control unit 43)

[0044] Control unit 43 controls the switching operation of each switching element Q1-Q6. Control unit 43 can be implemented, for example, by one or more dedicated hardware circuits and / or one or more processors (control circuits) operating according to a computer program (software). Processors include a CPU and memory such as RAM and ROM, which stores program code or instructions that cause the processor to execute various processes. Memory, or computer-readable media, includes any available media accessible by general-purpose or specialized computers.

[0045] The control unit 43 periodically turns on and off each switching element Q1 to Q6 based on commands from the air conditioning ECU 120. Specifically, the control unit 43 performs PWM control on each switching element Q1 to Q6 based on the commands from the air conditioning ECU 120. The control unit 43 generates a control signal using a carrier signal and a command voltage value signal. The control unit 43 then uses the generated control signal to control the on / off state of each switching element Q1 to Q6, thereby converting DC power into AC power.

[0046] (Regarding filter circuit 44)

[0047] Filter circuit 44 is provided between connector 36 and inverter circuit 42. Filter circuit 44 reduces noise contained in the DC power input from connector 36 to inverter circuit 42. Furthermore, filter circuit 44 reduces noise generated from inverter circuit 42 and flowing toward connector 36. The noise generated from inverter circuit 42 is, for example, noise generated by the switching operation of switching elements Q1 to Q6.

[0048] The filter circuit 44 is connected to the positive bus line Lp and the negative bus line Ln. Therefore, the filter circuit 44 is provided on the input side of the inverter circuit 42. The filter circuit 44 includes a smoothing capacitor 45, a coil 46, a first capacitor 47, and a second capacitor 48.

[0049] Smoothing capacitor 45 is an X capacitor connected in parallel with inverter circuit 42. Specifically, smoothing capacitor 45 is connected to positive bus line Lp and negative bus line Ln.

[0050] Coil 46 is, for example, a common-mode choke. It is located on the input side of converter circuit 42. Coil 46 has leakage inductance L. Leakage inductance L acts as a choke against normal-mode noise. Therefore, leakage inductance L and smoothing capacitor 45 are both components of a low-pass filter circuit that removes normal-mode noise. Thus, coil 46 reduces the noise contained in DC power. Therefore, filter circuit 44 removes both common-mode noise and normal-mode noise.

[0051] The filter circuit 44 includes two first capacitors 47. The two first capacitors 47 are connected in series. The space between the two first capacitors 47 is grounded to the vehicle body Ve via the housing 20. The two first capacitors 47 are connected in parallel to the connector 36. The two first capacitors 47 are connected in parallel to the coil 46. The two first capacitors 47 are located between the connector 36 and the coil 46.

[0052] The filter circuit 44 includes two second capacitors 48. The two second capacitors 48 are connected in series. The space between the two second capacitors 48 is grounded to the vehicle body Ve via the housing 20. The two second capacitors 48 are located between the coil 46 and the inverter circuit 42. The two second capacitors 48 are connected in parallel with the coil 46. The two second capacitors 48 are connected in parallel with the smoothing capacitor 45. The two second capacitors 48 are located between the coil 46 and the smoothing capacitor 45.

[0053] (Detailed Configuration of Circuit Board 41)

[0054] like Figure 3 As shown, the coil 46, the first capacitor 47 and the second capacitor 48 are mounted on the circuit board 41. Figure 3In the figure, for the sake of convenience, only one first capacitor 47 and one second capacitor 48 are shown. In addition, the smoothing capacitor 45 is also mounted on the circuit board 41, but Figure 3 In the figure, the smoothing capacitor 45 is omitted for convenience of explanation.

[0055] The circuit board 41 includes a first conductive pattern 51, a second conductive pattern 52, and a third conductive pattern 53. Furthermore, the circuit board 41 includes an insulating layer 54. The insulating layer 54 is formed, for example, of a plate-shaped glass epoxy resin. The first conductive pattern 51, the second conductive pattern 52, and the third conductive pattern 53 are formed from a sheet of copper foil. The first conductive pattern 51, the second conductive pattern 52, and the third conductive pattern 53 are formed into predetermined shapes. The first conductive pattern 51, the second conductive pattern 52, and the third conductive pattern 53 are provided on the surface of the insulating layer 54. The first conductive pattern 51, the second conductive pattern 52, and the third conductive pattern 53 are provided on the surface of the insulating layer 54 so as to be separated from each other to a degree that insulation between them can be ensured.

[0056] The first conductive pattern 51 is electrically connected to the inverter circuit 42. The first conductive pattern 51 has a first edge 51a that faces the second conductive pattern 52. Furthermore, the first conductive pattern 51 has a second edge 51b that faces the third conductive pattern 53. The second conductive pattern 52 is electrically connected to the connector 36. The second conductive pattern 52 has a third edge 52a that faces the first edge 51a of the first conductive pattern 51. Furthermore, the second conductive pattern 52 has a fourth edge 52b that faces the third conductive pattern 53. The third conductive pattern 53 has a fifth edge 53a that faces the second edge 51b of the first conductive pattern 51 and the fourth edge 52b of the second conductive pattern 52.

[0057] The first end of coil 46 is connected to first conductive pattern 51. The second end of coil 46 is connected to second conductive pattern 52. Thus, coil 46 electrically connects first conductive pattern 51 and second conductive pattern 52. Coil 46 electrically connects first conductive pattern 51 and second conductive pattern 52 by spanning between first edge 51a of first conductive pattern 51 and third edge 52a of second conductive pattern 52.

[0058] The third conductive pattern 53 electrically connects the first capacitor 47 and the second capacitor 48. The first end of the first capacitor 47 is connected to the second conductive pattern 52. The second end of the first capacitor 47 is connected to the third conductive pattern 53. Therefore, the first capacitor 47 electrically connects the second conductive pattern 52 and the third conductive pattern 53. The first capacitor 47 electrically connects the second conductive pattern 52 and the third conductive pattern 53 by spanning between the fourth edge 52b of the second conductive pattern 52 and the fifth edge 53a of the third conductive pattern 53.

[0059] The first end of the second capacitor 48 is connected to the first conductive pattern 51. The second end of the second capacitor 48 is connected to the third conductive pattern 53. Therefore, the second capacitor 48 electrically connects the first conductive pattern 51 and the third conductive pattern 53. The second capacitor 48 electrically connects the first conductive pattern 51 and the third conductive pattern 53 by spanning between the second edge 51b of the first conductive pattern 51 and the fifth edge 53a of the third conductive pattern 53.

[0060] A bolt 55 penetrates the third conductive pattern 53. The bolt 55 is screwed into the housing 20 to secure the circuit board 41 to the housing 20. The bolt 55 is electrically connected to the housing 20. Therefore, the bolt 55 serves as a ground. The third conductive pattern 53 is electrically connected to the bolt 55. Therefore, the third conductive pattern 53 is grounded. Furthermore, the third conductive pattern 53 is grounded to the vehicle body Ve via the bolt 55 and the housing 20.

[0061] (About Gap 56)

[0062] A slit 56 is formed in the third conductive pattern 53. The slit 56 extends from a portion of the fifth edge 53a of the third conductive pattern 53, located between the first capacitor 47 and the second capacitor 48, toward the bolt 55. Specifically, the slit 56 includes a first slit portion 56a and a second slit portion 56b. The first slit portion 56a extends from a portion of the fifth edge 53a of the third conductive pattern 53, located between the first capacitor 47 and the second capacitor 48, in a direction perpendicular to the fifth edge 53a. The second slit portion 56b extends from the end of the first slit portion 56a opposite the fifth edge 53a, along the fifth edge 53a toward the bolt 55. Thus, the slit 56 extends from between the first capacitor 47 and the second capacitor 48 toward the ground.

[0063] (Regarding the Current Path of the Third Conductive Pattern 53)

[0064] The cross-sectional area of ​​the current path between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 is smaller than when the slit 56 is not formed in the third conductive pattern 53. Furthermore, the current path between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 is longer than when the slit 56 is not formed in the third conductive pattern 53. Therefore, the impedance between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 is greater than when the slit 56 is not formed in the third conductive pattern 53.

[0065] Furthermore, the gap 56 makes the current path between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 longer than the current path between the second capacitor 48 and the bolt 55 in the third conductive pattern 53. Furthermore, the bolt 55 is located on the current path between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53.

[0066] (Regarding the insulating portion 57)

[0067] The space inside slit 56 is used as an insulating portion 57 to prevent noise flowing from inverter circuit 42 to third conductive pattern 53 via second capacitor 48 from flowing to first capacitor 47 without passing through bolt 55. Therefore, insulating portion 57 increases the impedance between first capacitor 47 and second capacitor 48 in third conductive pattern 53 compared to the impedance between second capacitor 48 and bolt 55 in third conductive pattern 53. Thus, insulating portion 57 includes slit 56. Thus, circuit board 41 includes insulating portion 57.

[0068] (effect)

[0069] Next, the operation of this embodiment will be described.

[0070] The noise generated from the converter circuit 42 is, for example, Figure 3 As shown by arrow A1 in FIG, the noise flows to the ground via the coil 46, the first capacitor 47 and the third conductive pattern 53. In addition, the noise generated from the converter circuit 42 is as shown in FIG. Figure 3 As shown by arrow A2 in FIG. 4 , the noise flows to the ground via the second capacitor 48 and the third conductive pattern 53. This prevents the noise generated by the inverter circuit 42 from flowing to the connector 36. As a result, the noise generated by the inverter circuit 42 is prevented from leaking to the outside via the connector 36.

[0071] Insulating portion 57 increases the impedance between first capacitor 47 and second capacitor 48 in third conductive pattern 53 compared to the impedance between second capacitor 48 and bolt 55 in third conductive pattern 53. Therefore, noise flowing from inverter circuit 42 to third conductive pattern 53 via second capacitor 48 is less likely to flow toward connector 36 via first capacitor 47. Furthermore, noise flowing from inverter circuit 42 to third conductive pattern 53 via second capacitor 48 is more likely to flow to ground. Consequently, noise generated from inverter circuit 42 is prevented from leaking to the outside via connector 36.

[0072] (Effect)

[0073] The following effects can be obtained in the above-described embodiment.

[0074] (1) The circuit board 41 includes an insulating portion 57. This insulating portion 57 increases the impedance between the first capacitor 47 and the second capacitor 48 in the third conductive pattern 53 compared to the impedance between the second capacitor 48 and the ground in the third conductive pattern 53. Consequently, noise flowing from the converter circuit 42 to the third conductive pattern 53 via the second capacitor 48 is less likely to flow toward the connector 36 via the first capacitor 47. Furthermore, noise flowing from the converter circuit 42 to the third conductive pattern 53 via the second capacitor 48 is more likely to flow toward the ground. Consequently, it is possible to suppress noise generated by the converter circuit 42 from leaking to the outside via the connector 36.

[0075] (2) A slit 56 extending from between the first capacitor 47 and the second capacitor 48 toward the ground is formed in the third conductive pattern 53. The insulating portion 57 includes the slit 56. Thus, the insulating portion 57 can be realized simply by forming the slit 56 extending from between the first capacitor 47 and the second capacitor 48 toward the ground in the third conductive pattern 53. Therefore, there is no need to add components such as new coils and capacitors to the circuit board 41 to suppress the leakage of noise generated by the inverter circuit 42 to the outside through the connector 36. As a result, the formation of new noise paths on the circuit board 41 due to the addition of components can be avoided.

[0076] (3) There is no need to add components such as new coils and capacitors to the circuit board 41 to suppress the leakage of noise generated by the inverter circuit 42 to the outside through the connector 36. Therefore, the size increase of the electric compressor 10 caused by adding components to the circuit board 41 can be avoided. Furthermore, since there is no need to change the layout or space of the circuit board 41 relative to the inverter housing chamber S2, the layout of the inverter housing chamber S2 can be more flexible.

[0077] (Change Example)

[0078] The above-described embodiment can be implemented by modifications as follows: The above-described embodiment and the following modifications can be implemented in combination with each other within a range that does not technically conflict.

[0079] In the embodiment, MOSFETs may be used instead of IGBTs as the switching elements Q1 to Q6. In this case, the diodes D1 to D6 are unnecessary.

[0080] In the embodiment, the insulating portion 57 may be formed by forming a through hole penetrating the circuit substrate 41 , for example, instead of the slit 56 .

[0081] In the embodiment, the number of first capacitors 47 is not particularly limited.

[0082] In the embodiment, the number of second capacitors 48 is not particularly limited.

[0083] In the embodiment, the coil 46 is not limited to the common mode choke coil.

[0084] In the embodiment, the compression unit 31 is not limited to the scroll type, and may be other types such as a piston type or a vane type.

[0085] In the embodiment, the electric compressor 10 is used in the vehicle air conditioner 100 , but the present invention is not limited thereto. For example, the electric compressor 10 may be mounted on a fuel cell vehicle and may compress air as a fluid supplied to the fuel cell through the compression unit 31 .

Claims

1. An electric compressor comprising: a compression portion configured to compress the fluid; an electric motor configured to drive the compression unit; an inverter device having a circuit substrate configured to drive the electric motor; and Connector, electrically connected to the power supply, The converter device comprises: a converter circuit configured to convert DC power input from the power supply via the connector into AC power; and a filter circuit located between the converter circuit and the connector and configured to reduce noise, The filtering circuit has: Coil; a first capacitor located between the coil and the connector; and a second capacitor located between the coil and the converter circuit; The coil, the first capacitor, and the second capacitor are mounted on the circuit board. The circuit substrate has a conductive pattern that electrically connects the first capacitor and the second capacitor. A bolt passes through the conductive pattern, and the first capacitor and the second capacitor are grounded via the same bolt. The circuit substrate includes an insulating portion configured so that an impedance between the first capacitor and the second capacitor in the conductive pattern is greater than an impedance between the second capacitor in the conductive pattern and the ground. The conductive pattern has a gap formed therein, extending from between the first capacitor and the second capacitor toward the bolt. A current path between the first capacitor and the second capacitor in the conductive pattern is formed to be longer than a current path between the second capacitor and the bolt in the conductive pattern. The gap constitutes the insulating portion.

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